Dam Alteration Identification by Extended Full-Waveform Inversion and Multiphase XFEM

通过扩展全波形反演和多相 XFEM 识别大坝改造

• 批准号: 395192382
• 负责人: Professor Dr. Tom Lahmer
• 金额: --
• 依托单位: Institut für Strukturmechanik (ISM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/395192382?language=en
• 关键词: Dam; Alteration; Identification; Extended; Full

Dams are important structures employed in the generation of hydro-electricity, provision ofwater supply and for flood defense. However, a large percentage of dams in operation today are more than 50 years old and as such the true condition of its structural integrity is not fully known.The deterioration of dams may result both from short term effects (e.g earthquakes, impact loads, etc) and from long term effects (e.g. aging, physical and chemical weathering, fatigue etc). Though these effects may not lead to an immediate collapse/failure of the dam, it is necessary, in order to ensure optimum performance of these structures, to identify quickly regions which may jeopardize the safety of the dam. Unfortunately the conventional methods are tedious, time consuming, expensive and inefficient.The method proposed in this project draws inspiration from the recorded success of full-waveform inversion (FWI) application in subsurface exploration and for non-destructive testing (NDT) in geotechnical engineering. Here not only do we intend exploiting the advantages of FWI in providing precise and reliable results but also the adaptation and extension of the method for damage identification in structures with dominant multiphase-multifield effects. In order to increasethe robustness and reliability of the proposed method, all the necessary phenomena surrounding the operation of the structure will be incorporated. Additionally, the stability (robustness) and the flexibility of the identification results will be increased be developing and applying a novel two-stage approach which consists of a combination of an extended Finite Element (XFEM)-based inversion and a subsequent FWI. The approach is general and may be applied even to other inverse seismic tomography problems. The proposed technique also takes advantage of recent advancements in computing technology, works in damage identification using XFEM, FWI, FEM-BEM hybridmethods and the optimal design of experiments (DoE). The goal is to efficiently and reliably detect anomalies in dams in a non-destructive manner and to minimize the sophistication and cost incurred by the application of full-waveform inversion (FWI) and conventional structural health monitoring techniques in dams.

水坝是用于水力发电、供水和防洪的重要建筑物。然而，目前运行的大部分大坝都有50年以上的历史，因此其结构完整性的真实状况并不完全清楚。大坝的劣化可能由短期效应（如地震、冲击荷载等）和长期效应（如老化、物理和化学风化、疲劳等）引起。虽然这些影响可能不会导致大坝立即倒塌/破坏，但为了确保这些结构的最佳性能，有必要快速识别可能危及大坝安全的区域。传统的反演方法繁琐、耗时、昂贵且效率低下，本文从全波形反演（FWI）在地下勘探和岩土工程无损检测（NDT）中的成功应用中得到启发。在这里，我们不仅打算利用FWI在提供精确和可靠的结果的优势，但也适用于结构的损伤识别的方法与占主导地位的多相多场效应的适应和扩展。为了增加所提出的方法的鲁棒性和可靠性，所有必要的现象周围的操作的结构将被纳入。此外，识别结果的稳定性（鲁棒性）和灵活性将增加开发和应用一种新的两阶段方法，该方法由基于扩展有限元（XFEM）的反演和随后的FWI的组合组成。该方法是通用的，甚至可以应用到其他逆地震层析成像问题。该方法还利用了计算技术的最新进展，采用扩展有限元法、模糊加权法、有限元-边界元混合法和最优试验设计法进行损伤识别。我们的目标是有效地和可靠地检测异常的大坝在一个非破坏性的方式，并尽量减少复杂性和成本所产生的应用程序的全波形反演（FWI）和传统的结构健康监测技术在大坝。